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Space Science

Study Provides Compelling Evidence of Single Impact Extinction Theory 382

ectotherm writes to tell us that a new study at the University of Missouri-Columbia claims to provide compelling evidence that a single meteor impact was the cause of animal extinction 65 million years ago. From the article: "MacLeod and his co-investigators studied sediment recovered from the Demerara Rise in the Atlantic Ocean northeast of South America, about 4,500 km (approximately 2,800 miles) from the impact site on the Yucatan Peninsula. Sites closer to and farther from the impact site have been studied, but few intermediary sites such as this have been explored."
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Study Provides Compelling Evidence of Single Impact Extinction Theory

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  • Re:65 million? (Score:5, Interesting)

    by sRev ( 846312 ) on Wednesday November 29, 2006 @05:51PM (#17040446)
    I read this yesterday and have been looking in occasionally to read the comments at the bottom. It looks like there must be some global creationist group that is directing traffic to the story, as every comment makes just that same arguement. I guess the creationist party line is that the "flood" wiped out the dinosaurs. That's a lot of water.
  • Re:65 million? (Score:3, Interesting)

    by ettlz ( 639203 ) on Wednesday November 29, 2006 @06:30PM (#17041074) Journal
    And yet, you are here on Slashdot.
    I do believe that grub is an anti-religious troll (read his sig, then read his posting history).
    And yet, you are here posting anonymously, thereby preventing us from examining your proclivities.
  • by MROD ( 101561 ) on Wednesday November 29, 2006 @06:36PM (#17041146) Homepage
    The problem with all these sedimentological studies is that the statistical period between large meteorite impacts and the systematic error in the dating of the sediments (using isotopic geochemistry) in addition to the ambiguity in the fossil record (and the dating errors in those sediments) means that it's guaranteed that you will find a correlation between any mass extinction and a large meteorite impact event.

    Around the K-T boundery there is not only the Chixalub impact but a large one in Germany and a couple of others which have been discovered, all within the dating error. Add to this that there's also the Decan Traps flood basalts being errupted, ocean currents changing as the north atlantic starts to open and the amount of flooded continental shelf decreasing hugely and you have several possible smoking guns.

    The evidence just isn't there currently to say why most of the dinosaur lineages died out (along with many sea reptiles and other oceanic creatures). In fact there is still a doubt as to when it actually happened and over how long a period. Ammonites, it seems, saw the meteorite coming.. about a million years before it hit.
  • Look, Up in the Sky! (Score:3, Interesting)

    by Doc Ruby ( 173196 ) on Wednesday November 29, 2006 @06:59PM (#17041472) Homepage Journal
    I want to know whether the meteor appeared from Earth to come from the direction of the Pleiades constellation that the Mayans would later prioritize in their studies with the world's most sophisticated pre-industrial astromomy.

    It's already an interesting coincidence that the people whose empire was built on the site of the most influential astronomical event in "recent" Earth history would have such sophisticated astronomy. I wonder what they discovered about the part of the sky from which the meteor seemed (to the dinosaurs) to appear. The Mayan name for the Pleiades is "Tz'ab" [google.com], "the rattlesnake's tail", which is pretty resonant with a meteorite that killed the lizards ruling the world.

    I also wonder if our current complex space sciences can reconstruct the path of the meteor from its origin, by studying the trajectories of the remaining solar system objects, and projecting back 65My to a slightly larger population. A lot has happened, but astronomers' deductions have made much of very little for quite some time.
  • Re:65 million? (Score:3, Interesting)

    by TheJorge ( 713680 ) on Wednesday November 29, 2006 @07:09PM (#17041582)
    I see a bigger problem with that statement.

    If we are to assume God did in fact create the universe and all its laws in such a way to make it look as though it's been around a lot longer than it has, and then gave us the tools of analysis and reason to "discover" these laws and the universe's history, who are we to thumb our noses at him and see through his giant fabrication? I mean, if He went to all this effort to make it look like there were dinosaurs 65 million years ago, carefully placing each photon and atom and what-not, we're pretty big jerks to dismiss all his efforts and say, "Yeah, that was nice with the fossil record and the carbon dating and all, but we know the truth. Good try with all that 'evidence' you made us." Even if you really know the secret truth that the universe has only been around 6500 years, lets not go and put a damper on God's efforts. Just go along with the rest of us when we say things like "Evolution" and "Big Bang"-- it'll make God a lot happier. And you don't want to make God angry.
  • Re:65 million? (Score:1, Interesting)

    by Anonymous Coward on Wednesday November 29, 2006 @07:15PM (#17041666)
    I'm not agreeing with it, but by definition, an omnipotent God could do literally anything.

    Could he microwave a burrito so hot that even he couldn't eat it? Either way he's not omnipotent!
  • Re:65 million? (Score:2, Interesting)

    by ArcherB ( 796902 ) on Wednesday November 29, 2006 @07:18PM (#17041722) Journal
    65 million years is crazy-talk, that's 64,994,000 years before God made the Earth!

    So a lot of people believe in Creationism. What's really sad is that even MORE people believe that 9-11 was an inside job, even though there is actually more evidence of creationism! Some examples include: lack of lunar dust, the Big Bang theory breaks the first law of thermodynamics, life breaks the second law of thermodynamics, descriptions of dinosaurs living and walking around in The Bible and so on.

    Personally, I do believe the universe was created some 13-20 billion years ago but neither me nor anyone else can prove by who or how. I just suggest that you and the rest of the slashdotters take a little time to actually read the arguments of Creationism before you immediately dismiss it and ridicule those that believe it as a matter of faith and/or science. I've met good Christians with multiple doctorates in scientific disciplines such as physics, nanotechnology and quantum mechanics. I think it is safe to assume that these people are smarter than the vast majority of slashdotters who frequently mock their intelligence because of their religion.

    Finally, as a Christian myself, I humbly ask that slashdotters stop seeing every article that deals with dinosaurs, evolution/Darwin, stem cells or genetics as an excuse to slap me in the face with it. The only thing worse that pushing your religion on others is trying to take other's religion away.

  • by ebers ( 816511 ) on Wednesday November 29, 2006 @08:01PM (#17042218)
    A skeptical reply:

    > I want to know whether the meteor appeared from Earth to come from the direction of the Pleiades constellation that the Mayans
    > would later prioritize in their studies with the world's most sophisticated pre-industrial astromomy.

    Yes, but lots of civilizations have placed importance on the Pleiades. Perhaps because they look so cool.

    > It's already an interesting coincidence that the people whose empire was built on the site of the most influential astronomical
    > event in "recent" Earth history would have such sophisticated astronomy.

    Yes, but several ancient civilizations developed advanced astronomy. I suspect ancient civilizations are more likely to develop astronomy if:

    They have a way to record numbers and do arithmetic.
    They have a written language that allows them to record observations.
    They have substantial city-states sustained by intensive farming, and
    That farming relies (possibly via irrigation) on rainfall that comes at specific times each year.

    > also wonder if our current complex space sciences can reconstruct the path of the meteor from its origin, by studying the
    > trajectories of the remaining solar system objects, and projecting back 65My to a slightly larger population.

    Not going to happen. We would need accurate measures of the trajectory of the earth before and after the collision to determine the momentum, and thus direction, of the meteor. In principle, if we knew everything that happened in the solar system since that time to a very high accuracy, we could run Newton's equations backward and find the trajectory of the earth after the event.

    Yup, I'm a doubting Thomas.
  • Re:65 million? (Score:3, Interesting)

    by Maxo-Texas ( 864189 ) on Wednesday November 29, 2006 @09:33PM (#17043252)
    And what kind of a sick liar of a god would do that?

    Should you worship such a god?

    Which is more plausible. that such a god exists... or that the evidence we can repeatably measure is correct.
  • by Jonas the Bold ( 701271 ) on Wednesday November 29, 2006 @09:38PM (#17043318)
    I'm not going to write a complete rebuttal, but to start with, a 747 has a wingspan of ~55 meters. Not that a 12 meter wingspan isn't big, but it is not the size of a 747. Second, a Pterosaur is not a bird. It's a different evolutionary branch entirely. Just because birds can't achieve that sort of wingspan, doesn't mean no flying animal can. Imagine if birds had died out and there were no bats, you'd find a fossil of a seagull and say gravity must have been lower because you can't breed a flying insect that size. Third, look at the build of the larger birds, like vultures or eagles or albatrosses. The larger the birds get, the smaller thier bodies get in proportion to their wings. Now look at Pterosaur skeletons. The pattern holds. Now think, for a moment, about what would happen if gravity were lower. Air would be much thinner. The earth would orbit further from the sun. I assume we're talking about a major change in gravity here that would allow "birds the size of 747s". If gravity were that low earth probably wouldn't even have liquid water. Now here's the part I hope you won't take as me giving anything up, I'm not, but EVERYONE agrees the sun has electromagnetic phenomenon. It simply does. Science believes it's caused by the conductive plasma the sun is made of working as a dynamo caused by plasma convection from the sun's core, where energy is produced by fusion. What your electric universe theory suggests is that the sun is nothing but a big gas discharge light bulb, and there's a multiple exowatt current being run through it. As for the Big Bang theory not explaining the sun's corona, those are sort of different scales, aren't they? The big bang theory also doesn't explain how ants communicate. It's not supposed to. It explains the formation of the universe, not phenomenon in individual stars. Asteroids orbits are not all circular and not eliptical. Every orbit is eliptical, with the sun at one of its focci. Comets' orbits tend to be very eliptical. Asteroids less so, mostly. But they're all elipses, of varying degrees. The grand canyon was caused by lighting because it's shape looks like a bolt of lighting. Give me a break.
  • Re:65 million? (Score:4, Interesting)

    by Artifakt ( 700173 ) on Wednesday November 29, 2006 @10:35PM (#17043856)
    Natural Selection has EVERYTHING to do with the First Spark of Life".

    1. Standard evolutionary theory says that a lower mutation rate, (down to some minimum that is greater than zero) actually increases selection speed. That sounds counter-intuitive, but it is straight from Dawkins and similar sources. One reason here is that mutations are occuring in organisms that are already pretty close to perfectly adapted to their environments or they'd be dead. The few mutations that are improvements are generally small improvements, that take generations of testing to prosper. A high enough mutation rate, and a new mutation overwrites the last one before the first had time to be tested. To see this a little more clearly, just imagine a mutation that makes an annual type plant a little better able to resist drought. If droughts only happen in that area about every 20 years, the mutation only helps a carrier survive every twenty generations or so. There are several other arguements for this point, which can be found in the Dawkin's The Selfish Gene or The Blind Watchmaker, or in a typical college textbook on the subject.
    (Anyone who doubts this is standard theory is welcome to write somebody such as Dr. Dawkins and ask, or for God's sakes read a little. Usually when I get this far, someone insists this isn't the standard theory of evolution at all, and proposes some kind of Lysenkoism as the standard instead. I am very sick and tired of proposing this and having people who think evolution means the X-men try to prove I'm wrong.).

    2. Modern organisms use DNA, with both advanced error correction and mutation reduction. One form of correction is sexual reproduction, by using a second copy of most genes. One form of reduction is putting the DNA in a central nucleus where it is less exposed to chemical mutagens.

    3. Fully modern DNA in sexual organisms has been around for at least 700 Million years (see Dr. Simon Conway Morris's estimates for the age of the earliest Ediacaran fauna. If he's not THE greatest still living expert on this, he's at least number 2.).

    4. Less modern DNA, but still with error protection in the form of nucleated cells, has been inside the oldest fossil eukarotes since, at the absolute very least, 2.1 Billion years ago (again Morris's timetable). That's also about half the age of the Earth (4.2 Billion years).

    5. Really primative DNA with no correction or protection, has been found, again at the very least, as far back as the first stromatolites (2.9 billion years). Most paleontologists (admittedly not all), point to earlier fossils, as early as 3.5 billion years old, for the first DNA based organisms.

    6. DNA is believed to have developed from RNA. RNA is still used by most life as a messenger chemical, but is only found as a heredity chemical in some very primative viruses. The error rates for RNA are well known, and indicate evolution must have been proceeding very slowly, even compared to the most primative DNA based life. The living record agrees with this, as do extensive tests comparing generalized eukarotes with all surviving types of non-eukarotes. While it's not as universally agreed by biologists as the earlier points, it's still generally agreed that RNA did predate DNA. You can find a few recognized biologists who don't support this last point, but they are a distinct minority, under 5%.

    7. This means, we have counted back to within about 700 million years of the time Earth formed, just for the three stages of DNA based life. That's about 84% of all the time we have to explain life. The RNA dominant period, when evolution was much slower, has to fit into that last 16%. Whatever came before RNA has to fit into what's left after RNA gets its share, and so on.

    8. By the standard theory's best guess, there are at least a dozen stages, each with more primative molecules involved, going back to the beginnings of life. The earliest ones might have been non-living clay-like substances, where natural selection operated only
  • Re:65 million? (Score:4, Interesting)

    by shutdown -p now ( 807394 ) on Thursday November 30, 2006 @05:17AM (#17046564) Journal
    There are other ways around that paradox. The one I tend to like most is that "a stone the God cannot lift" is not definable in a meaningful way. It simply doesn't mean anything, much the same as "result of division of 1 by 0" (the latter is not infitity BTW... it's nothing, as in, there's simply no such thing), or, even simpler, a "square circle".

    Can God create a "square circle" or a "triangle with four sides"? The fallacy is that of assuming that the answer of canCreate(x) should be either true or false. For some values of x, you just get an ArgumentException, which is really neither ;)

    P.S. And no, I'm not a Christian.

  • by init100 ( 915886 ) on Thursday November 30, 2006 @12:35PM (#17050554)
    there may be other craters out there, but there is certainly nothing else out there like Chicxulub.

    Oh? What about the Shiva crater [wikipedia.org]?

    The Shiva crater, along with the Boltysh crater [wikipedia.org] and the Silverpit crater [wikipedia.org], are all dated to about the same time as the Chicxulub crater [wikipedia.org], and this brought up the multiple impact theories.

The unfacts, did we have them, are too imprecisely few to warrant our certitude.